Roller covered with rubber or other resilient material



sept. 9, 1930. c. H. GRAY 1,775,392

ROLLER COVERED WITH RUBBER ORv OTHER RESILIBNT IATERIAL Filed 0st. 24,1927 W fzcgj.

INVENTCS! Patented Sept.. 193() unir-ED vSTATES PrviiaNi-'Ir` OFFICE lCHRISTIAN HAMILTON GRAY, or LONDON, ENGLAND EOLLEE covEaEnwIriIRUBBER-OE OTHER EEsILIENr IIA'rEnLaL Application led October 24, 1927,Serial No. 228,163, and in Qreat Britain November 19, 1928.

This invention consists in improvements in or relating to rollerscovered with rubber or other resilient material suchv as aroused Linpaper-making machines, printing machines and in machines for manyl othermanufactures and trades.

It has been found that the coverings of i such rollers tend to wear verymuch. more rapidly adjacent the ends of the rollers than at the centreportions thereof. This Jis particularly the case in rubber-coveredrollers used in paper-making machines.

The object of this invention is to provide a roller covered with rubberor'other resilient material, the covering of which wears a proximatelyuniformly across substantial y the whole lwidth of the surface of theroller.

It has been found by the present rinventor that-the excessive wear ofthe covering of the rolleradjacent the ends thereof is due to theresistance to deformation of thecovering of the roller adjacent saidends being different from that of the covering at the centre poi;- tionof the roller. Heretofore the end portions and the centre portions ofrollers have been covered with resilient material having er se the sameresistanceto deformationf ut since the end portions of the covering arenot sup orted on both sides by adjacent portions o the covering, as isthe centre portion,

the covering of the covered roller has been much less resistant todeformation adjacent said ends than at the centre of the f roller.

Accordin to this invention a roller covered lwith ru ber or otherresilient material is constructed with resilient devices situated on theroller for supporting the endsofthe covering in such a manner as toensure that resistance to deformation of the covering is roximatel4uniform across substantially the whole wi th of the roller.

Thev required uniformity of resistance to `deformation may be obtainedin a number of was-. l 15in theaccompanying drawings whichillustrateconstructions of roller according to the resent invention Figure 1 is alonlgitudinal sectionoil-part of one side of a-ro Figure 2 is a similarview of another construction of roller, and v Figure 3 1s a similardiagrammatic view of one 'end of a third'construction.

Figure 1-shows a modification of thecon- 55 parts struction shown inFigure 3.

Like vreferences indicate throughout the drawings.

A is a portion of the like body ofthe roller,

B is the hard rubber base-covering thereon, vand C is the Outer coveringencircling the greater the resistance or hardness hence the drawingsindicate at the places marked H that the material of the cover Cat-those places is of a chosen hardness or resistance,

and that at the' places marked in sequence H1, lH2, HS'H the hardless orresistance is greater in inverse proportion to their nearf ness to theadjacent end of the roller, reaching-Ia maximum at H4'.

' Figure ltheletters' H1, H2, Hs, H4 in addition to indicating relativeresistances or hardnesses, as aforesaid, are used to indicate alsoseparate' rings H1, H, H3, H4

piece forming an endfor supporting the covering C.

These circumferential rings of material such as rubber oir-H4l may be ofebonite) of suitable resistance to deformation substantially greaterthan thatv of the material constituting the Outer Acovering C, aresecured by vulcanization or otherwise in position against each end ofthe covering C. The

characteristics of the said rings and their size depend on thedifference in resistance to deformation that would formerly have existedbetweenl the portion ofthe covering C adjacent the ends and that at thecentre of the coverin The rings will constitute end por- '05 tions w ichcan be tapered, as illustrated in Figure 1, to a degree which is suitedto the quality and other characteristics of the said covering.

In Figuure' to deformation of the 65 .materiaL i. e. the denserthesection-lining the laced` side by side to constitute a compoun end-80 2 the covering C adjacent tothe 10 ends of the rollervin the Widths Wthereof may consist of material which at H1, H2, H3, His, per se, moreresilient to deformation than is, per se, the material at the points Hof the covering. In this case the material may be graduated frommaterial at H4 of, per se, the greatest resistance to deformation at theextreme ends of the roller, to material at H of resistance todeformation which is, per se, the same as that at the centre of theroller at a substantial distance from said ends. c

In Figure 3, floating rings R of rigid material, such as hard rubber,Wood or even metal, are positioned to bear against theends of theresilient covering C of the roller, the said rings being spring-pressedthereagainst by a plurality of springs S positioned between said ringsand pressure-plates'P secured to the shaft or to the body portion oftheroller and extending transversely in relation to the axis thereof.

Figure 4 shows a similar construction to that shown in Figure 3, whereinthe springs S are replaced by a single helical spring S1.

The portion of the covering C occupying the Width W thereof in Figure 2and also the device occupying the Width W of the roll in Figures l, 3and 4 are devices for the purpose of affording to the end-faces of thecovering C support to such a degree against the tendency of the ends todeform under pressure applied to the circumference of the said rollerthat these end-faces, and such sections of the ends of the covering asare parallel to the endfaces, are as much supported as is an parallelsection situated nearer to the mid le of the Width of the covering.

In a roller constructed as above described with reference to Figure 1,the undermentioned dimensions and data have been found to givesatisfactory results Length of the roller A 13 ft. 9 inches.

Covered diameter of the same 25%= inches. Thickness of hard rubberplicable to rollers covered with rubber, it is v understood that it isnot limited thereto and may be applied to rollers covered with otheryresilient material.

I claim i l. The combination of a roller and a resilient coveringtherefor that comprises a central section and end sections, each ofwhich end sections is constituted by a plurality of zones of resilientmaterial each of uniform resilience throughoutits cross-section and saidzones of each end section progressively decreasing in resilience fromthe inner to the outer of the zones for the purpose described.

2. The combination of a roller and a resilient covering therefor thatcomprises a central section and end sections which are tapered in such amanner that the diameter of the resilient covering at its ends is lessthan the diameter ofthe said central section, each of which end sectionsis constituted by a plurality of zones of resilient material each ofuniform resilience throughout its cross-section and said zones of eachend section progressively decreasing in resilience from the inner to theouter of the zones for the purpose described.

In testimony whereof I aiix my signature.

CHRISTIAN HAMILTON GRAY.

The four rings H1, H2, H, H4 are each fths of an inch and are chamferedolf at an angle of 221/2 degrees.

Plastometer hardness figures for the various parts are The relativediameters of roller A and a top rjolller which rested upon it were inthis case ill)

